Posted on 09/09/2018 3:11:37 PM PDT by BenLurkin
https://www.forbes.com/sites/jillianscudder/2017/02/08/astroquizzical-slow-solar-sail/
the infrared from Proxima Centauri (a red dwarf) would work to slow it down, but it would take time, and with wings this big the odds of damage from encountering some rocks is pretty great.
In the laser-boosted scenario, as given a number of years ago (I read it in the 1990s I think) the brakes would be applied by a leading craft. The probe would be bringing up the rear. As the solar energy became strong enough (assuming everything in working order), the laser in the leading craft would acquire the probe craft and apply the needed deceleration. The leading laser craft would just keep on sailing, finally crashing into a muslim wedding in a baby food factory built hundreds of years in the future, construction made possible by currently unimagined or unavailable transportation technology, along with witless 7th century superstition.
Well the speed of light is 186,000 miles per second! So top that... 186,000 miles per second = 669600000 miles an hour..
Thanks for attempting a real response this time, but after the laser was turned on, the front spacecraft would accelerate away from the following spacecraft. The laser’s ability to slow down the following spacecraft would continually diminish over time.
It wouldn't take long, so it would work; the other method from then was to make the leading probe a big mirror on one side -- it would turn and the big-assed laser in orbit around our Sun would shoot the beam, which would reflect against the trailing probe. But of course, none of this has been demostrated.
So, are they contracting with the Space Force to supply ships for the journey? Would be a lucrative scam.
Supposedly the mass of the material will increase as speeds approach speed of light....will energy come from atomic powered lasers....solar energy prob too little at that distance from Sun...cool idea...but I have heard of these things for 20 to 30 years...
Remember the ion engines....where is Diet Smith now that we need him?
Again, that would constantly accelerate the front craft away from the following craft. It would require ever-increasing precision in aiming the front craft's beam or positioning the following craft, and would result in an ever-decreasing received beam strength.
It wouldn't take long.
I strongly doubt that. What is your source?
I suspect that when the numbers are all added up, this Rube Goldberg scheme will be shown not to work. But, I could be wrong. In any case, we're a long way from your "duh," which I hope was a joke.
I hear you - way back when, I hit a pheasant while going 84 mph - fortunate it hit the bumper and that it was an old style car ('61 Chevy Bel Air) where the bumpers really were...bumpers. Felt like I had hit a deer from the jolt, left feathers in a cloud that obscured the road behind me and it was a job to get all the bits and pieces from around the headlight as they had squirted inside the fender area to some tough to reach places....not enough left for the stew-pot.....
How would these solar sails tack. Thy would need a keel with something to offer some resistance.
The physicists who worked all this stuff out are my sources. Dunno at this point who they were, nor do I care. Your only source is yourself. But obviously this subthread is far more important to you than to me.
I wouldn’t want to hit a grain of sand at that speed..........................
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